1. Field of the Invention
This invention relates to a self-contained hydraulic power unit and more particularly to a power unit which does not require hydraulic power supplied from an external power source. More particularly, this invention relates to a self-contained hydraulic power unit that may be utilized on a grain trailer or the like to power the lift cylinder on the dump unit, power the conveyer, power the hydraulic floor, or power the end gate.
2. Description of the Related Art
Trailers or the like are frequently used to transport grain or other commodities from one location to another. Frequently, the trailers include a lift cylinder to enable the body to be pivotally moved from a non-dumping position to a dumping position. Further, the trailer or the like may have a conveyor or hydraulic floor associated therewith. Additionally, in some instances, the end gate for the trailer is powered by a hydraulic actuator such as a hydraulic cylinder or hydraulic motor. Inasmuch as the trailers do not normally have a power source, it is necessary that the tractor or truck pulling the trailer have a PTO and hydraulic system with a reservoir to power the hydraulically operated components on the trailer. Many times, the tractors and trucks do not have PTO""s thereon. Other systems on the market utilize a small gas or diesel engine to pump oil to the hydraulic actuators. Further, some systems utilize electric over hydraulic systems. These electric systems plug into an electrical source to power the hydraulic actuators such as hydraulic cylinders or hydraulic motors. Such systems are expensive.
A self-contained hydraulic power unit is disclosed for powering one or more hydraulic actuators such as hydraulic cylinders or hydraulic motors. The power unit of this invention is ideally suited for use on a grain trailer or the like including a hydraulic cylinder for raising and lowering the dump body, a hydraulic actuator for raising or lowering the end gate of the trailer, a hydraulic actuator for operating a conveyor on the trailer, or a hydraulic actuator for operating the hydraulic floor of the trailer. The power unit comprises a hydraulic pump having inlet and discharge sides; a valve means having inlet, outlet, and return sides; a hydraulic reservoir having inlet and outlet sides; the inlet side of the hydraulic reservoir being fluidly connected to the return side of the valve means; the outlet side of the hydraulic reservoir being fluidly connected to the inlet side of the hydraulic pump; a hydraulic accumulator having an inlet/outlet port; the discharge side of the hydraulic pump being fluidly connected to the inlet/outlet port on the accumulator for accumulating hydraulic fluid under pressure within the accumulator; the inlet/outlet port of the accumulator being fluidly connected to the inlet side of the valve means for supplying hydraulic fluid under pressure to the valve means; and the outlet side of the valve means being fluidly connected to the hydraulic actuator whereby the valve means may be operated to provide pressurized hydraulic fluid from the accumulator to the hydraulic actuator to operate the same. In one embodiment of the invention, the hydraulic pump is battery operated. In another embodiment, the hydraulic pump is wheel driven by a wheel on the trailer as the trailer is moved from one location to another.
It is therefore a principal object of the invention to provide a self-contained hydraulic power unit for powering a hydraulic actuator such as a hydraulic cylinder or hydraulic motor.
Still another object of the invention is to provide a self-contained power unit which may be mounted on a trailer or the like for powering the hydraulic components thereon.
Still another object of the invention is to provide a self-contained hydraulic power unit which may be either battery driven or wheel driven.
These and other objects of the invention will be apparent to those skilled in the art.